Oak Grove School District No. 20 was established in 1867 in Lincoln Township, Neosho County, the same year Neosho and Labette counties were formed from the original county of Dorn, making Oak Grove one of the oldest of more than 200 school districts that eventually occupied the combined area of those two counties. Its first schoolhouse was a log structure located one half mile northeast of here in Section 25, Township 30 South, Range 20 East, with a cemetery beside it; remnants of that cemetery remain, but the log schoolhouse is gone. The stone schoolhouse at this site was built in 1877 in Section 36, Township 30 South, Range 20 East. The cemetery here has been in use since the early 1870s, while the earlier cemetery in Section 25 ceased to be used after 1876, and it contains many pioneers of the early Oak Grove community, including the Padgett family, donors of the 1877 school property, Hiram Humphrey, donor of the new cemetery site, and George Hewitt, the earliest recorded school board chair. Over the years Oak Grove served not only as a school but also as a center of social, political, and religious activity in Lincoln Township and along the Neosho-Labette county line, and a Sunday School picnic held here in 1904 drew more than two thousand people. Oak Grove was last used as a school in the 1959-1960 academic year.